On April 26, 1986, the world’s worst nuclear accident happened at the Chernobyl plant near Pripyat, Ukraine, in the Soviet Union, that has continued to haunt the world even after the 30 years of the accident. It happened during a test to see how the plant would operate if it lost power.
On December 8 2016, the United Nations General Assembly adopted a resolution designating April 26 as International Chernobyl Disaster Remembrance Day.
Here’s what happened at Chernobly
On April 26 at about 1:23 am, reactor no. 4 overheated and exploded. It happened during a test to see how the plant would operate if it lost power.
The day before the Chernobyl nuclear disaster, plant operators were preparing for a one-time shutdown to perform routine maintenance on reactor number 4. In violation of safety regulations, operators disabled plant equipment including the automatic shutdown mechanisms.
At 1:23 a.m. on April 26, when extremely hot nuclear fuel rods were lowered into cooling water, an immense amount of steam was created, which created more reactivity in the nuclear core of reactor number 4.
The resultant power surge caused an immense explosion that detached the 1,000-ton plate covering the reactor core, releasing radiation into the atmosphere and cutting off the flow of coolant into the reactor.
A few seconds later, a second explosion of even greater power than the first blew the reactor building apart and spewed burning graphite and other parts of the reactor core around the plant.
After the explosion, the first westerners to know were Swedish Nuclear plant workers whose sensor’s read high levels of radiation. Sweden sent out the first alert that something was happening. It wasn’t until the world pointed their satellites towards what is now northern Ukraine, that we realized what had happened.
The explosion released a radioactive cloud that ended up killing several thousands. Radioactive isotopes were transmitted by dust particles floating in air and falling to ground. Radioactive iodine is dangerous as it can quickly be accumulated in thyroid gland and leads to thyroid cancer and death
Ukraine Chernobyl Union estimates present death toll from disaster at almost 734,000. The meltdown created a fear of nuclear power that still exists today